This invention is related to the beneficiation of sulfide and precious metal ores, preferably by froth flotation.
Froth flotation is one of the most widely used processes for beneficiating ores containing valuable minerals; see e.g. "Flotation: Theory, Reagents and Ore Testing" by Ronald D. Crozier, Pergammon Press 1992; also "Surface Chemistry of Froth Flotation" by Jan Leja, Plenum Press, 1982. It is especially used for separating finely ground valuable minerals from their associated gangue or for separating valuable minerals from one another. In froth flotation, a froth or a foam is generally formed by introducing air into an aqueous slurry of the finely ground ore, typically in the presence of frothing or foaming agent. A chief advantage of separation by froth flotation is that it is a relatively efficient operation at a substantially lower cost than many other processes.
A wide variety of compounds are taught to be useful in froth flotation e.g. as collectors, frothers, modifiers, depressants, dispersants, pH regulators, and various promoters and additives; e.g. see "Reagents for Better Metallurgy," edited by P. S. Mulukutla, published by the Society for Mining, Metallurgy and Exploration, Inc, 1994. A single compound may perform more than one function. The specific additives used in a particular flotation operation are usually selected according to the nature of the ore, the conditions under which the flotation will take place, the mineral sought to be recovered and the other additives which are to be used in combination therewith.
The use of various collectors e.g. for ore beneficiation is disclosed in U.S. Pat. Nos. 4,556,482; 4,595,493; 4,587,013; 4,511,464; 4,605,519; 4,618,461; 4,676,890; 4,684,459; 4,699,711; 4,702,822; 4,732,668; 4,735,711; 4,780,557; 4,789,392; 4,797,202; 4,793,852; and 4,822,483. Alkylated diaryl oxide monosulfonate collectors are disclosed in U.S. Pat. No. 5,015,367.Dialkyl aryl monosulfonate collectors are disclosed in U.S. Pat. No. 5,173,176. A phosphate flotation process employing various aryl disulfonates is disclosed in U.S. Pat. No. 4,172,029. Depressants for silica or siliceous gangue are disclosed in U.S. Pat. No. 5,057,209. Both depressants and collectors may be combinations of substances as in U.S. Pat. Nos. 4,514,292; 4,309,282; and 5,171,427. The use of sulfonates as a substitute for, or along with, xanthate or dithiophosphate in copper sulfide ore flotation is disclosed in U.S. Pat. No. 3,827,557. An apatite flotation process employing combinations which include alkyl aryl sulfonate is disclosed in U.S. Pat. No. 3,405,802. Flotation of heavy metal oxides is disclosed in U.S. Pat. No. 2,861,687. Aryl sulfonates useful as depressants for froth flotation of micaceous minerals are disclosed in U.S. Pat. No. 3,214,018. Use of dinonyl naphthalene disulfonic acid in solvent extraction of metals is disclosed in U.S. Pat. No. 4,166,837 and U.S. Pat. No. 4,255,395. All patents, patent applications, books and articles mentioned herein are hereby incorporated herein by reference.
Despite the large number of compounds and combinations of compounds, those skilled in the art are constantly searching for new ways to improve ore beneficiation. Frequently, froth flotation is a very large-scale operation, so that beneficiation improvements of 0.5% or 1% may provide dramatic increases in plant economics. Accordingly, it is an object of the instant invention to provide new compositions, effective to provide improved beneficiation of a particulate sulfide or precious metal ore in a froth flotation process. It is another object to provide methods of using new compositions, effective to provide improved beneficiation of a particulate sulfide or precious metal ore in a froth flotation process.